“What causes vomiting after anesthesia?”

Surgery , anesthesia and the patient susceptibility

Anesthetic gasses and opioids can both cause nausea.

There are several different things that can cause vomiting. Most of the modern anesthetics themselves tend not to cause vomiting as in the past. Laparoscopic surgery carries a higher risk of nausea as the bowel is often pushed about in the belly. Opiates such as remifentanil used intraop cause nausea. Post-operative pain medications can cause nausea. If you drink more than 2 large coffees a day or the equivalent caffeine, caffeine withdrawal is often related to headaches and nausea. Different phases of the menstrual cycle can also predispose you to nausea. Most anesthesiologist routinely give IV anti-nauseant medications intraoperatively to reduce the incidence of nausea.
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